Simple monocarboxylic acid esters of vicinal alkanediols are known compounds useful as foam-inhibitors in washing compositions, as described in U.S. Pat. No. 3,993,605. This patent however describes fatty acid and benzoic acid mono and diesters of non-terminal vicinal alkanediols having 12 to 32 carbon atoms.
Copending, commonly assigned U.S. Patent application Ser. No. 837,691 also describes fatty acid and benzoic acid monesters of terminal and non-terminal vicinal alkanediols having from 8 to 20 carbon atoms, which are alkoxylated to give low-foaming surface-active compounds useful as clear-rinse agents in mechanical dishwashers.
In contrast to the production of oil-in-water emulsions, only a limited number of emulsifying agents are available for producing cosmetic emulsions of the water-in-oil type and, moreover, the best of these emulsifying agents are becoming increasingly scarce. Even nowadays, wool fat and its derivatives are still some of the most important bases for emulsifying agents for producing creams of the water-in-oil type. However, despite their uncontested advantages, wool fat and its derivatives, such as lanolin, have certain disadvantages. Thus, conventional water-in-oil emulsifying agents based on wool fat and its derivatives impart a strong characteristic odor to the creams prepared with these substances. This in turn, requires strong perfuming which frequently cannot be tolerated by persons having sensitive skin. However, this influencing of the quality of the cream by a strong characteristic odor is not only peculiar to wool fat and its derivatives, but also extends to lanolin-free water-in-oil emulsifying agents based on animal sterols, particularly such emulsifying agents based on cholesterol. Furthermore, low-molecular weight emulsifying agents, together with the effective substances of the cream, can be absorbed by the skin, which is not desirable in all cases.
In addition to the said emulsifying agents based on wool fat, wax alcohols and sterols, the most widely known water-in-oil emulsifiers for cosmetic purposes include the oleic acid esters of various polyols, such as glycerine, pentaerythritol, trimethylolpropane and sorbitol. However, due to the unsaturated character in their acid component, the oleic acid esters have various disadvantages with respect to their technical use, so that there is a genuine need for new and suitable water-in-oil emulsifying agents.